This research effort is designed to develop microencapsulated disulfiram capable of being administered by intramuscular injection. The purpose is to obtain a long-acting injectable disulfiram formulation capable of providing effective sensitization to alcohol for periods greater than two weeks, possibly for several months. The capsule wall, a bioabsorbable polymer like poly (lactic acid), will be designed to prevent direct contact of disulfiram particles with the body fluid and thereby prevent any irritation effects that might otherwise occur. Since this wall must provide controlled disulfiram release over a prolonged period, extensive in vitro and in vivo evaluations of release behavior will be carried out. In the latter case, this will involve monitoring blood levels of disulfiram or its active metabolite, and evaluating effectiveness of the injected disulfiram on the test animal, which is the rat. Histological examination of the muscle tissue at the injection site will be made over a period of time to determine if the capsules cause any adverse effects.